Proper method for cord drops?

[mdshunk]

After having made up many hundreds of cord drops in an industrial setting during my career as an electrician, I'm still puzzled about some of the finer points of making a "compliant" cord drop. There are several questions to which answers continue to elude me.

1) CORD TYPE. Does a buss drop cord have to be listed "Buss Drop Cord" (with the heavy strain members inside the jacket) or can it be ordinary SJO or SJT?

2) SUPPORT. Normally, the point where the cord drops from the bar joist I generally use a Kelllems grip hanging off an eye bolt or bridle ring. I think this makes good sense. Others have advised me that this is too expensive and a couple of heavy zip ties will due just fine. Is this true? At times, I have even hung the Kellems grip from a drawbar spring for the code required strain relief. Is the drawbar spring necessary, or is the Kellems grip enough to provide the required strain relief?

3) CORD TERMINATION. When the cord is terminated in a cord cap, does the cord cap need to have the special Kellems grip designed for use with a cord cap? Can the cord have a handy box (or 4" square) hanging off the end with a duplex receptacle installed? Can the cord have an FS box with strain relief cord conector hanging off of it with a duples installed? Can a cord drop be hard wired to fastened in place equipment? Can a cord drop be permanently wired to serve receptacles on a workbench or work table?

4) REPAIRS/SPLICES. Can a buss drop cord be repaired with butt splices and rubber/plastic tape in much the same manner that extension cords and appliance cords are permitted to be repaired?

[Wgoodrich]

1) CORD TYPE. Does a buss drop cord have to be listed "Buss Drop Cord" (with the heavy strain members inside the jacket) or can it be ordinary SJO or SJT?

REPLY; Depends on the distance dropped and type connector light duty or heavy duty. Much of this is in a gray area the AHJ must rule on. Most are done by using heavy usage SO cords.

2) SUPPORT. Normally, the point where the cord drops from the bar joist I generally use a Kelllems grip hanging off an eye bolt or bridle ring. I think this makes good sense. Others have advised me that this is too expensive and a couple of heavy zip ties will due just fine. Is this true? At times, I have even hung the Kellems grip from a drawbar spring for the code required strain relief. Is the drawbar spring necessary, or is the Kellems grip enough to provide the required strain relief?

REPLY; If less than say 10" a strain relief and SO cord is all that is required in light industrial use and not in a type H [hazardous] location. The Code does require strain relief. However it is normally required to be a UL listed product unless specifically approved by the AHJ. They have a strain relief/box connector combined that is mounted in a knock out of a cover plate with a locknut and hte chinese finger is manufactured as part of the connector to the box. No further support is normally used. If the AHJ rules abuse is expected a steel support cable or a cable with manufactured interior steel support is required by that AHJ. Check with your supplier for Racon box end strain reliefs. All built as one unit.


3) CORD TERMINATION. When the cord is terminated in a cord cap, does the cord cap need to have the special Kellems grip designed for use with a cord cap? Can the cord have a handy box (or 4" square) hanging off the end with a duplex receptacle installed? Can the cord have an FS box with strain relief cord conector hanging off of it with a duples installed? Can a cord drop be hard wired to fastened in place equipment? Can a cord drop be permanently wired to serve receptacles on a workbench or work table?

REPLY; Whew you ran away with your questions in 3 !! Ha ha. Remember this again is within the gray area that is within the AHJ to make a final ruling on the subject. First the cord cap must be with strain relief per Code. Many plugs can be bought again with a manufactured UL listed strain relief in its design which is acceptable. The also make a Kellums that slides onto the rubber cord with a loop that can be jack chain connected to a loop that is built into the cord plug to support this plug.

Remember any junction box must be securely supported and secured to the structure per Code rules. Again this is an AHJ call as to what he will accept.

Yes a drop cord is allowed to serve a fastened in place utilization equipment permenantly attached, but not a portable utilization equipment that can move around.

Yes a drop cord if properly install may serve a work bench or work table. Many are installed with a spring or even a spring loaded retractable cord to work with. You can buy a retractable UL listed drop cord unit with a trouble light attached and plugs in that light to work with. they are normally hung from a "U" bolt attached to the celing then plugged into a ceiling receptacle. Then the worker pulls down the cord to work and it locks in that position while working then when done the pull the cord and it retracts to stay clear of work area until needed again. This is often light duty usage for work areas even in the middle of a room.

In my jurisdiction I will allow a single plug only. If you want a multiple plug unit then it needs to be plugged into that single plug. I do not allow a nonsupported junction box creating a multiple receptacle design. Way too much weight and a speggeti mess is then created if this was allowed. Not safe in my opinion or meeting intent of Drop Cord rules.

4) REPAIRS/SPLICES. Can a buss drop cord be repaired with butt splices and rubber/plastic tape in much the same manner that extension cords and appliance cords are permitted to be repaired?[/font][/size][/QUOTE]

REPLY; UL lists and it is sold what is called a cord juntion box. This UL listed product is a round cavity with interior strain relief just like a cord plug is made only with room to make your splice within this UL listed cord junction kit. Not expensive. Check with your supplier for availability in your area or ask your AHJ for advice where one can be obtained. No an open taped or heat shrink splic is approved by the NEC. Any splice must be contained in a containment listed for its use.

Hope this helps

Wg